腫瘤科－平滑肌腫瘤（Oncology）

Leiomyosarcoma are rare tumors of small intestine which arise from the muscularis mucosa or muscularis propria. The most common site of LMS in the small intestine is jejunum followed by ileum and then duodenum. The common presentations include abdominal mass, abdominal pain or overt gastrointestinal bleeding. They are mainly seen in 6th decade of life with slight male preponderance. Preoperative diagnosis of small intestinal tumors is difficult, especially differentiating between benign and malignant tumors. For LMS in small intestine, recent review of literature revealed that CT and MRI-enterography and enteroclysis are good options.Cases of superficial lesion which can be missed by both CT and MRI, can however be detected by water capsule endoscopy with a detection rate of around 80%. Histologically LMS resembles like GIST, however they are CD117 and CD34 negative by immunohistochemistry and positive for smooth muscle antigen (SMA) and desmin. When these tumors are more than 5 cm they commonly spread hematogenously to liver (65%), other GI organs (15%), lung(4%). It also has the capability to spread via lymphatics (13%) or via peritoneal route (18%). The only effective treatment for small intestine LMS is surgery. The primary tumor should be excised radically, including a wide resection of the mesentry. Response to chemotherapy is doubtful, and there is no role for radiotherapy. Therefore, metastasectomy, if possible, should be considered. Large phase II and III studies combining docetaxel and gemcitabine yielded impressive response rates in LMSs (mostly of uterine origin). However, others were not able to confirm the efficacy of this combination. Recently, trabectedin showed response rates up to 56% in LMSs, and it appeared to be especially useful in far-advanced and metastatic LMSs after failure of the combination of anthracyclines and ifosfamide.

Leiomyosarcoma (LMS)1 areis a  rare tumors of small intestine which arise from the muscularis mucosa or muscularis propria. The most common site of LMS in the small intestine is the jejunum, followed by the ileum and then duodenum. The common presentations include abdominal mass, abdominal pain, and2 or overt gastrointestinal bleeding. They are mainly seenobserved3 in 6th decade of life with slight male preponderance. The Ppreoperative diagnosis of small intestinal tumors is difficult, especially in terms of differentiating between benign and malignant tumors. For LMS in the small intestine, a recent review of literature revealed that computed tomography (CT) and magnetic resonance (MR)I- enterography and enteroclysis are good detection4 options. Cases of superficial lesions, which can be missed by both CT and MRI imaging, can however be detected by water capsule endoscopy, with a detection rate of aroundapproximately  80%. Histologically, LMS resembles likegastrointestinal stromal tumorGIST,; however they areit is negative for5  CD117 and CD34 negative by immunohistochemistry and positive for smooth muscle antigenactin6 (SMA) and desmin on immunohistochemistry. When these tumors are more than 5 cm, they commonly spread hematogenously to liver (65%), other gastrointestinalGI organs (15%), and the lungs (4%). It They also has have the capability to spread via the lymphatics system (13%) or via peritoneal route (18%). The only effective treatment for LMS in the small intestine LMS 7is surgery. The primary tumor should be excised radically, including a wide resection of the mesentry. Response to chemotherapy is doubtfulunknown, and there is no role for8of radiotherapy.  Therefore, metastasectomy, if possible, should be considered.  Large phase II and III studies combining docetaxel and gemcitabine yielded impressive response rates forin LMSs (mostly of uterine origin). However, others were not able to confirm the efficacy of this combination. Recently, trabectedin showed response rates up to 56% forin LMSs, and it appeared to be especially useful in far-advanced and metastatic LMSs after failure of the combination of anthracyclines and ifosfamide.

Leiomyosarcoma (LMS)1 areis a  rare tumors of small intestineintestinal tumor, which arises from the muscularis mucosa or muscularis propria. The most common site of occurrence of 2LMS in the small intestine is the jejunum, followed by the ileum and then duodenum. TheIts common presentations manifestations3 include abdominal mass, abdominal pain, and4 or overt gastrointestinal bleeding. They are mainly seenobserved5 in the 6th decade of life with slight male preponderance. In general, the The Ppreoperative diagnosis of small intestinal tumors such as LMSs is difficult, especially in terms of differentiating between benign and malignant tumors. For LMS in the small intestine, 6According to a recent review of literature revealed that review computed tomography (CT) and magnetic resonance (MR)I- enterography and enteroclysis are good 7detection options. Cases of superficial modalities for the assessment of LMS.  Superficial lesions, which can be missed by both CT and MRI imaging, can however be detected by water capsule endoscopy, with a detection rate of aroundapproximately  80%. Histologically, LMS resembles like8gastrointestinal stromal tumorGIST,; however, on immunohistochemical analysis, they areit is has been found to be negative for9  CD117 and CD34 negative by immunohistochemistry and positive for smooth muscle antigenactin (SMA)10 and desmin on immunohistochemistry. When these tumors arethe size of LMS is 11more than 5 cm, they commonly spread it can hematogenously spread to the liver (65%), other gastrointestinalGI organs (15%), and the lungs (4%). It TheyIt can also has have the capability to spread via the lymphatics system (13%) or via peritoneal route (18%). The response of LMS to chemotherapy is unknown, and radiotherapy does not play a role in the treatment. Therefore, surgery is the only effective treatment for LMS in the small intestine. LMS 12is surgery. The primary tumor should be excised radically, including a with wide resection of the mesentry. Response to chemotherapy is doubtfulunknown, and there is no role forof13 radiotherapy.  Therefore, metastasectomy, iIf possible, metastasectomy should be considered.  Large phase II and III studies combiningtrials involving the combination of docetaxel and gemcitabine yieldedhave reported impressive response rates forin LMSs (mostly of uterine origin). However, others weresome studies have14 not been able to confirm the efficacy of this combination. Recently, trabectedinTrabectedin has recently showed response rates of up to 56% forin LMSs, and it appeared to be especiallyparticularly useful inagainst far-advanced and metastatic LMSs after failure of the combination of anthracyclines and ifosfamide, combination therapy.